More than three billion people are at risk from indoor air pollution because of the heating or cooking fuels they use.

VOA: special.2010.02.01

and they offer leisure class that's indoor rock climbing.

学校有休闲课，就是室内攀岩。

攀岩的刺激 - SpeakingMax英语口语达人

At indoor centers, climbers have many different paths they can use to get to the top of the walls.

VOA: special.2009.12.09

President Obama is said to be considering replacing the bowling alley with an indoor basketball court.

VOA: special.2009.05.08

Each year, nearly thirty million people use indoor tanning beds in the United States.

VOA: special.2010.07.06

He linked the indoor and outdoor spaces in a very beautiful way.

VOA: special.2009.12.13

By nineteen sixty, Arthur had won the National Junior Indoor Championship.

VOA: special.2010.02.07

It would also save money on indoor air cooling costs.

VOA: special.2009.06.19

Past these rooms we find an indoor swimming pool.

VOA: special.2009.11.16

The Nickelodeon Universe is an indoor theme park.

VOA: special.2010.08.13

Miz Bowman works at an indoor climbing center.

VOA: special.2009.12.09

There is also indoor climbing.

VOA: special.2009.12.09

They found that indoor air pollution causes pulmonary diseases that kill an estimated Outdoor air pollution accounts for another 470 thousand deaths.

VOA: standard.2010.04.07

BAC and 10 other organizations offer services and classes there, in everything from how to clean a home, to proper indoor plumbing etiquette, to employable skills.

VOA: standard.2010.07.22

Many residents live in shacks without running water or indoor sanitation.

VOA: standard.2010.03.21

"Traditional environmental risks are those that face largely the poor in China, risks like drinking water contaminated with infectious organisms or highly polluted indoor air from people burning wood or other dirty fuels inside homes without chimneys."

VOA: standard.2010.04.07